Publication Year

2018

Publisher

International Whaling Commission

Abstract

At the 2016 IWC Scientific Committee meeting, it was agreed that an annual or bi-annual report on the Bering-Chukchi-Beaufort Seas (BCB) bowhead whale stock would be submitted that summarizes various health-related data (George et al. 2016). This summary is intended to be helpful for providing ancillary but pertinent information for informing management recommendations and tracking the status of the BCB population. This report is the 2nd of the series (George et al. 2017a) and summarizes general information on population indices, whale health and hunter observations of bowhead whales. We provide new information on (1) population size and trends, (2) adult survival rate, (3) acoustic index of relative abundance of migrating whales, (4) calf production (aerial surveys), (5) pregnancy rates of landed adult females, (6) body condition and whale lice burden of landed whales, (7) proportion of landed whales showing evidence of feeding, (8) proportion of landed whales with injuries consistent with line entanglement, killer whale attacks and/or ship strikes, (9) non-harvest related mortality of bowhead whales, (10) pathological findings from postmortem examinations and disease screening surveys of landed whales, and (11) hunter observations. Important population metrics such as population size and trend, calf production and crude pregnancy rates continue to show positive or stable trends for this stock. While climate warming is a major concern, the various metrics described in this review (in particular population size and trend; calving rate; body condition) suggest that to date, bowheads are not being harmed by sea ice retreat.